little things

One-off tech demos and test ROMs for NES

This repository will contain several tech demos for Nintendo Entertainment System that I've produced over more than a decade prior to 2019.

• 768-byte level editor
• Action 53 (mapper 28) big CHR RAM
• Action 53 (mapper 28) comprehensive test
• Anti-DiskDude header cleaner
• BNROM and AOROM size and mirroring test
• Boing 2007: squashing the background using mistimed VRAM reads
• Boolean Beakers
• ca65 macros reimplementing 6502 mnemonics
• CHR compression through pixel RLE
• Compatibility Benchmarks for 2001
• Concentration Room Emblem Designer prototype
• Convergence
• DAC nonlinear volume
• DPCM Split: generate a stable raster split without external timer hardware
• EQ test: pink noise and sine sweep generators
• Eighty: read buttons on the NES Four Score accessory
• Fairydust Editor with Compressed Output
• FamiTracker module to video renderer
• File extractor for Family Computer Disk System (FDS) images
• FME-7 big PRG RAM
• FME-7 IRQ acknowledgment
• gmewav: render anything libgme or DUMB plays to a WAV file
• GNOME vs. KDE: Battle of the Desktops: Bingo-inspired 2-player game
• Hello World program produced while learning ca65
• Insane Game: incomplete attempt to port the TI-83 version of SameGame
• IRE tiny: port of the IRE (brightness level) test of 240p Test Suite to run on a minimalist devcart
• Mapper 78 submappers: test for handling of nametable mirroring in ROMs intended to run on the Uchuusen and Holy Diver cartridge boards
• Math library: multiply, divide, square root, binary to decimal
• Meece: first NES program to use a Super NES Mouse
• Metatile engine using 32x16-pixel cells
• MMC3 big CHR RAM
• MMC3 save data viewer
• Nibbles: the snake game people have loved since the QBasic era, which ended up on a few famiclones' built-in pirate multicarts
• OAM reset quirk: 2 sprites will be missing after Reset
• Password save
• PAL chroma phase: investigate how a TV comb filter combines scanlines in the video from various NES and famiclone models
• Port test for famiclone assembly
• Pretendo and other fake logos: generate entropy without a button press to randomly choose a parody logo to drop into the Game Boy boot ROM intro
• Raw PCM Hello: compare PCM to DPCM and attempt playback through pulse channels' volume registers
• RGB121: display 16-color images on an NES using pseudo-interlacing
• Russian Roulette
• Software parallax: use bit shifting to rotate background tiles horizontally
• Sound drivers that never progressed far
• Sprite 0 hit interactive test
• Sprite Cans
• Sprite scaling: real-time shrinking is possible using lookup tables
• Tall Pixel: stretch an image vertically by 150%
• Telling LYs?: sub-frame input timing test
• Text to spectrogram
• Tuning table generator for NSD.Lib
• Vaus Test: read the Arkanoid controller
• Volume tester: Relative volumes of APU channels
• VWF terminal
• Zapper lag tests
• Projects that never proceeded past pixel art prototypes

Many of them have patches to their build system to help them build under Python 3 and late-2010s versions of cc65. (To get set up to build, see the instructions for nrom-template.) The build process is tested under Debian and Ubuntu distributions of the GNU/Linux operating system and may need changes to work on Microsoft Windows.

Most should be under the zlib license or an equivalent GNU all-permissive license, though this merits an audit.